STREAM BANKS

Stream bank erosion contributes sediment directly to streams. Unlike other sediment sources, there is 100% delivery. Property owners are concerned about property losses into the stream. Causes are complex, but are related to natural stream channel movement, the clearing of land, and tree removal upstream and/or along stream edges.

When land is cleared of vegetation and/or paved, rainwater runoff is more rapid. This rapid runoff of many individual parcels of land results in more water in a shorter period of time in streams. To accommodate this rapid volume increase, streams either expand outward eroding the banks, or downward digging into their beds.

The CRA has implemented several streambank restoration projects in the area. Bank shaping, complemented by the use of geotextiles, can create stable streambanks capable of resisting the erosional forces of high flows. Projects like the ones shown below can reduce the input of sediment into the river, which is a pollutant that has been shown to reduce biodiversity as well as water quality.